C# 继承：静态与非静态字段

Question

我有一个库基类 (Controller) 和三个继承自 Controller 的子类（Sensor、Output 和 Environment），其中：

public class Controller
{
   private SerialPort serial;
   private Sensor sensorSettings;
   private Output outputSettings;
   private Environment environmentSettings;       


   protected Dictionary<int, string> ErrorDescriptions
   { get{ this.errorDescriptions; } }

   protected SerialPort ControllerSerialPort
   { get{ this.serial; } }

   protected Sensor SensorSettings
   { get{ this.sensorSettings; } }

   // The other sub-class get properties.

   protected string SendReceive(string controllerCommand)
   { ... }

   ...
 }

 public class Sensor : Controller {...}
 ... // Other sub-classes

我的问题是：我应该将errorDescriptions 设为静态吗？这些错误描述不会因控制器而异（即静态），但我不确定在继承的类中会发生什么。我必须在Sensor 类中将它们称为Sensor.errorDescription，还是仍然是Controller.errorDescription？

编辑

哇，我刚刚意识到我搞砸了。我认为应该是这样的：

private abstract class ControllerBasics
{
   protected SerialPort serial;  // The serial port to communicate with the controller.
   protected Dictionary<int, string> errorDescriptions = new Dictionary<int, string> {...};   // Possible errors for the controller (known and fixed). Won't change from controller to controller.
   public enum Sensors {One, Two, ...};   // Possible sensor selection.

   public string SendReceiveCommand(string command){...} // Method to send string command over "serial".       
}

public class OverallController : ControllerBasics // The controller class.
{       
   // Add top-level controller settings.
   private string controllerName = "Controller1"; // Have a property to get/set.
   private bool controllerON; // Controller on/off. Have property to get/set.
   ... // Other similar fields and methods.

   // Used to "sort" the controller's many settings/functions.
   private SensorSettings sensorSettings;  // Have get/set properties for these so I could do the following: overallControllerInstance.GetSensorSettingsProperty.SetActiveSensorCount(5);
   private OutputSettings outputSettings;
   private EnvironmentSettings environmentSettings;

   public OverallController(string name, string comPort, ...)  // Constructor.
   {
      // Basic settings initialization.
      // Create serial port.
      this.sensorSettings = new SensorSettings(this.serial);
      this.outputSettings = ...
}

public class SensorSettings : ControllerBasics // Class to hold the controller's specific sensor settings and their respective get/set methods. Not a new type of controller.
{
   private int activeSensorCount; // Have public method to get/set.
   ... // Others.

  public void SetActiveSensorCount(int sensorCount)
  {
     // Send command using inherited SendReceive().
  }
  ... // Others.
}

public class OutputSettings : ControllerBasics   // Same logic as SensorSettings.
{
   private string units; // Have public method to get/set.
   ... // Others.

  public string GetUnitType()  // Meters, mm, um...
  {
     // Send command using inherited SendReceive().
  }
  ... // Others.
}

public class EnvironmentSettings : ControllerBasics   // Same logic as SensorSettings.
{
   ...
}

因此，如果在 ControllerBasics 中定义的 errorDescriptions 是已知且固定的（并且在所有派生类中都需要），我应该将其设为静态还是应该将其保留为受保护并且每个派生类都有自己的字典（即 this.错误描述）？

Answer 1

只有 一个 静态变量，不管你有多少子类。它是否意味着因子类而异，还是真正是一个全局映射？如果是后者，那么静态变量是合适的。如果不是......好吧，有多种选择，但您需要告诉我们您使用地图的目的。

Answer 2

如果您只需要字典的一个实例而不是需要，请将其更改为受保护的静态。此外，您应该使用ConcurrentDictionary 代替线程安全。

在派生类中，您可以使用Controller.errorDescription 访问该字段

Answer 3

好吧，您的派生类将看不到私有成员。为此，您需要一个受保护的成员或属性。在类中，您可以将其称为 errorDescriptions 或 this.errorDescriptions。

我会非常警惕有一个静态的、受保护的成员变量，它不是线程安全的，并且可以被派生类改变。那只是自找麻烦。